Gear grinding machines have been conventionally provided to grind a gear with a grinding wheel after heat treatment of the gear and thereby efficiently finish a tooth surface of the gear. In such gear grinding machines, repeated grinding wears out the grinding wheel, deteriorating the sharpness thereof. Accordingly, after a predetermined number of gears are ground, dressing needs to be performed on the worn grinding wheel to restore edges thereof to sharp edges.
Therefore, the conventional gear grinding machines are provided with a dressing device which dresses the worn grinding wheel with a dresser. Such a gear grinding machine provided with the dressing device is disclosed, for example, in Patent Document 1.